Abstract : An axially symmetric pressure wave expanding with constant speed along an infinitely long cylindrical shell submerged in an inviscid, incompressible fluid of infinite extent is considered. Shell-fluid interaction problems involving loads moving with constant speed have been solved by transforming to a coordinate system moving with the wave speed at the wave front. Such solutions are referred to as steady-state because an observer traveling with the wave speed would presumably see a constant pattern both ahead and behind the wave front. In this paper, the complete initial value problem is formulated and the solution is presented as the sum of a complementary and a particular solution. The steady-state solution is also constructed.